Method for the construction of a cutoff wall



Jan. 30, 1951 T. OGNIBENE 2,539,670

METHOD FOR THE CONSTRUCTION OF A CUTOFF WALL Filed Sept. 5, .1946 2 Sheets-Sheet l IN VEN TOR. TITO OGNIBENE ATTORNEY Jan. 30, 1951 T. OGNIBENE METHOD FOR THE CONSTRUCTION OF A CUTOFF WALL Filed sept. 5, 194e 2 Sheets-Sheet 2 FIG. 7.

INVENTOR.

TITO OGNIBENE ATTORNEY Patented Jan. 30, 1951 METHOD FOR THE CONSTRUCTION F A CUTOFF WALL Tito Ognbene, Milan, Italy- Application September 5, 1946, Serial No. 694,950 In Italy September 25, 1945 (Cl. (i1-31) 8 Claims.

The present invention relates to the construction of a cut-off wall for adam structure or a sheet-piling or the like.

An object of the present invention is to provide a cut-off wall built by a series of contiguous piles or pillars tightly interconnected with each other by mechanical means so as to form a watertight structure.

Another object of the present invention is to provide a cut-off wall wherein an element or elements used for building up of the cut-ofi" wall can be used for the arrangement of a ltering system within the cut-off wall during the construction thereof.

A further object of the present invention is to provide a cut-off wall which may be readily connected with sheet-piling.

With the above and other objects of the invention in view, the invention consists in the novel method, construction, arrangement and combination of various elements and parts, as set forth in the claims hereof, certain embodiments of the same being described in the specification and being illustrated in the accompanying drawings forming part of this specification, wherein:

Fig. 1 is a top plan view, partly in section, of a prefabricated pillar arranged between the positions of two piles to be cast-in-place for the construction of a cut-olf wall in accordance with the invention,

Fig. 2 is a top plan view of a diiferent embodiment of a prefabricated pillar according to the invention,

Fig. 3 is a top plan View similar to that shown in Fig. 2, wherein, however, filler material is placed into recesses of the prefabricated pillar,

Fig. 3a is a vertical sectional View taken on line a-a of Fig. 3,

Fig. 4 is a top plan View of a further embodiment of a prefabricated pillar according to the invention,

Fig. 5 is a top plan view of still another-embodiment of a prefabricated pillar according to the invention,

Fig. 6 is a top plan view, partly in section, of a further embodiment of a prefabricated pillar according to the invention,

Fig. 6a is a side elevational View of the lower portion of a prefabricated pillar as shown in Fig. 6,

Fig. '7 is a top plan View of another embodiment of a prefabricated pillar according to the invention,

Fig. 7a is a vertical sectional view taken on line b--b of Fig. 7,

Fig. 8 is a top plan view of a series oi prefabricated pillars in a section of a cut-oli wall according to the invention, said pillars being provided with means for connection with sheet-piling,

Fig. 8a is a side elevational View of the arrangement of prefabricated pillars shown in Fig. 8, and

Figs. 9-12 are top plan views, partly in section, of various diierent embodiments of prefabricated pillars according to the invention.

Referring now to Fig. l illustrating the invention in its simplest form, A generally indicates a reinforced prefabricated pillar which is inserted into a tube or pipe C previously driven into the ground in any suitable manner. The preabricated pillar A is provided with a series of stirrups E embedded into the material, preferably concrete, of the pillar-A. Said stirrups E extend transversely of the longitudinal axis of the pillar A and their ends project from the pillar at opposite sides thereof. The projecting ends of the stirrups E are protected by removable shields S of steel. The shields. S are curved in such a manner that, after removal of the tube C enclosing the pillar A, they may serve as guides for the tubes C and C when the latter are driven into the ground, preparatory to the casting of the adjacent piles P and P". Moreover, owing to said curved shape of the shields' S, the tubes C and C subsequently driven into the ground may intersect the space previously occupied by the tube C, so that overlapping portions L having a cross-section of the shape of a lens are formed.

When concrete is poured into a tube C' or C, for example into the tube C' for preparing a pile P' of concrete or reinforced concrete, the tube C and the shield S adjacent to said tube C are withdrawn at the same time, so that the concrete leaving the tube C at the lower end thereof may perfectly and fully envelop the stirrups E and may perfectly and fully engage the side surface of the prefabricated pillar A from which the stiriups project so as to form an integrated structure including the preiabricated pillar A and the cast-in-place pile P. Thus, a fully watertight connection is obtained between the prefabricated pillars and cast-in-place piles used for the integrate structure of the cut-off wall.

The prefabricated pillar A may be made in the shape of a full or hollow or tubular body.

In the embodiment shown in Fig. 2, a hollow prefabricated pillar A is used. Said hollow pillar A is provided with a center bore V and has two longitudinal recesses Lu of substantially semi- 'is Ylikewise made of two separate pieces.

circular cross section at opposite side surfaces thereof. Apparently, the hollow shape of a pillar A may be chosen for reducing the Weight thereof. Said hollow shape, however, may also serve another useful purpose.

As shown in Figs. 3 and 3a, a suction pipe R forming a part of a ltering system is inserted into the center bore f the piQlar A. The lower end of said suction pipe R communicates with a filter tube F embedded into a iilter bed Z prepared below the pillar A. Thus, it is possible to lower the underground water level without the use of a special lter well drilled outside the cut-oit wall.

The longitudinal recesses Lu of semi-circular cross-section likewise contributing to a reduction of the weight of the prefabricated pillar A may also be used for the formation of two additional filter columns. As shown in Fig. 3a, during the withdrawal of the tube C filtering material G is filled 'into said two recesses Lu, whereby two filter columns are formed connecting the upper underground water strata with the lower underground water stratum, the water of which is sucked by the ltering system communicating with the filter bed Z varranged below the pillar A. Thus, the filter columns may be effectively used for a drainage of the ground. If desired, one or more pipes may be placed into 'the lter columns which may be 4used'for pressing grout or other packing material into the ltering material so as to obtain an increased waterightness of the cut-off wall and toY ill intervening spaces between the cut-of.r` wall and the ground or an adjacent structure.

As shown in Fig. 4, a prefabricated pillar ao- -vcordi'ng to the invention may be made of two separate symmetrical parts A1 and A2, which may be displaced relative to each other in a direction lperpendicular to theV longitudinal axis of the `In such a case, each protecting shield S l After the withdrawal of the tube C enclosing the pillar pillar.

portions A1 l and A2, said two portions are moved 'away from each other by any suitable means to such an extent, that their outer round surfaces occupy atleast the same position previously occupied by the'outer surface of the round tube C.

lThe concrete subsequently iilled into the tubes C'. C for'casting the piles P', P will also penetrate into the space thus formed between the portions A1 and'Az of the pillar.

According to Fig. 5, the protecting shields S may also be made of two relatively movable parts, so that,after the withdrawal of the tube enclos- "ing the pillar A, the protecting shields may be extended in width, whereby their outer edges previously contacting or nearly contacting the insidev of the tube now occupy the position previously occupied by the outer surface of the tube.

The prefabricated pillar may be inserted into Athe ground or may be driven into the ground by and protecting shields S has a cutting shoe D at its lower end, by means of which the penetration 'into the 'ground may be facilitated. Flushing pipes T are inserted into the recesses Lu. Material disintegrated and loosened by the liquid ejected from the flushing pipes may be removed through the center bore V of the pillar A.

rihe prefabricated pillars may be ofgreater length than the piles cast-in-place. For example, when a cut-oi wall according to the invention is used in submarine construction, the cast-inplace piles P may reach only up to thebottom of a river or the like while the pillars A may reach beyond the bottom of the river and may even extend above the level of the water as illustrated by Figs. 8 and 8a. If desired, the pillars A may be extended by means of beams of steel or concrete anchored in or connected to the body of the pillar proper. The extensions of the pillars A may constitute elements of the cut-off structure and may be used for the construction of a watertight sheeting of a cofferdam.

The prefabricated pillar may be provided with means for a ready connection with a sheet-piling of steel. According to Fig. 9, for example, va section of a sheet-pile cut along its length ispartially embedded into the body of the pillar A, so that its flanged part projects therefrom 'and renders possible an easy Vconnection with the ange of a normal sheet-pile of the same profile.

As shown in a U-shapedv beam U may be inserted into and connected with the body of the pre-fabricated pillar A, if desired, so as to -form a channel or groove of a coiferdam.

i'furtiinnore, any otner suitable prole iron, for example prolile iron F of the shape shown Fig. il, may be inserted into vand connected with the oi the preiabricated pillar A so as to form such a channel or groove.

According to the embodiment shown in Fig. i2, the pr "fabricated pillar A carries also flat iron sheets l i addition tothe stirrups E. Said'flat iron sheets extending in the rlongitudinal 'direction oi the pillar A arepartially embedded into the material or" the piilar Yand project partially from the saine sides of the pillar as the stirrups The iron sheets, likewise, protected by the shields S, serve to in'iprovethe watertightness oi the cut-oi wall.

Furthermore, the prefabrifatedpillar rmay be provided with lateral and/or'central grooves zor ribs extending longitudinally ci the pillar at the sides from which the ende or" the stirrups project. Said grooves or ribs are arranged for engagement with the shields so 4asto:prevent same from an undesired lateral displacement which might be caused by the driving in'of anadjacent tube, whereby the watertightness fof the finished cutwali may be iurther'inoreased.

What claim is:

l. A method for the construction of a cut-oli wall comprising the steps cli-driving a rlrst'tube into prefabricatedpillar into acing removable shields into s id t1 'ie at side" of' ^i.d='pillai', withdrawing said driving a1s`ec'on`d tube'in'to the ground in such a manner that it "inte'rsects the space previously occupied "by saidV irst tube and is adjacent such a shield, pouring coner'ete'into sai second tube, and withdrawing'substantially sir ltaneously said second tubeand t'headjacent fneld during the poui'ing-oiconcrete into said ond tune.

l e hod the construction o' a cut-off compri ing the steps Aof driving a irst'tube into the ground, placing a preiabricated lpiilar into said fir ing element wall st tube, saidpreiabricated pillar ll'iavs projecting from sides'thereof, 'placing removable shields into said first tube at the sides of said pillar with said projecting elements so as to cover same by said shields driving a second tube into the ground in such a manner that it intersects the space previously occupied by said rst tube and is adjacent such a shield, pouring concrete into said second tube, and withdrawing substantially simultaneously said second tube and the adjacent shield during the pouring of con crete into said second tube.

3. A method for the construction of a cut-off wall comprising the steps oi driving a rst tube into the ground, placing the assembly of a pre-- fabricated pillar having elements projecting from sides thereof and of shields covering said projecting elements and being slidably engaged with said pillar into said first tube, withdrawing said first tube, driving a second tube into the ground in such a manner that it intersects the space f previously occupied by said first tube and is adjacent such a shield, pouring concrete into said second tube, and withdrawing substantially simultaneously said second tube and the adjacent shield during the pouring oi concrete into said second tube.

4. A method for the construction of a cut-off wall comprising the steps of driving a rst tube into the ground, placing a preabricated pillar including two individual component parts into said iirst tube, placing removable shields into said rst tube at sides of said pillar, withdrawing said first tube, spreading said component parts of said pillar apart from each other so as to provide for a space between same, driving a second tube into the ground in such a manner that it intersects the space previously occupied by said rst tube and is adjacent such a shield, pouring concrete into said second tube, and withdrawing substantially simultaneously said second tube and the adjacent shield during the pouring of concrete into said second tube.

5. A method for the construction of a cut-oit Wall comprising the steps of driving a rst tube into the ground, providing a filter bed in the lower portion of said rst tube, placing a prefabricated hollow pillar into said rst tube on top of said lter bed, inserting a nltering pipe of a ltering system into said hollow pillar in communication with said lter bed, placing removable shields into said rst tube at sides of said pillar, withdrawing said rst tube, driving a second tube into the ground in such a manner that it intersects the Space previously occupied by said first tube and is adjacent such a shield, pouring concrete into said second tube, and withdrawing 6 substantially simultaneously said second tube and the adjacent shield during the pouring of concrete into said second tube.

A method for the construction of a cut-oli wall as claimed in claim 5, wherein a preiabricated hollow pillar having recesses at sides free from said shields is placed into said rst tube, inserting ltering material into said recesses so as to build filter columns connecting with said filter bed.

sembly or a prefabricated hollow pillar having elements projecting from sides thereof and oi shields covering said projecting elements and being slidably engaged with said pillar into said rst tube on top of said iilter bed, inserting a ltering pipe of a filtering system into said hollow pillar in communication with said iilter bed, withdrawing said rst tube, driving a second tube into the ground in such a manner that it intersects the space previously occupied by said first tube and is adjacent such a shield, pouring concrete into said second tube, and withdrawing substantially simultaneously said second tube and the adjacent shield during the pouring of concrete into said second tube.

3. A method for the construction of a cut-off wall as claimed in claim 7, wherein a prefabricated hollow pillar having recesses at sides free from said shields is placed into said iirst tube inserting ltering material into said recesses so as to build lter columns connecting with said lter bed.

TITO OGNIBENE.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 969,343 Conkling Sept. 6, 1910 1,447,254 Langworth Mar. 6, 1923 1,665,798 Sipe Apr. 10, 1928 1,829,463 Weber Oct. 27, 1931 2,090,720 Ball Aug. 24, 1937 2,329,223 Schmidt Sept. 14, 1943 FOREIGN PATENTS Number Country Date 11,268 Great Britain 1898 

